Abstract - To examine the effects of tree species on soil nitrogen (N) mineralization we monitored rates of soil nitrogen mineralization and nitrification using the buried bag incubation method in 37-year-old Japanese larch (Larix leptolepis Gordon), pitch pine (Pinus rigida Mill), and oak (Quercus serrata Thunb) stands on a similar soil in central Korea. Litter and mineral soil (0-15 cm) were incubated for 45 day intervals from 1 September 1994 to 31 August 1995. Mean daily N mineralization rates were significantly different among sampling dates and the tree species. Annual net N mineralization and nitrification were also significantly different among the tree species; the annual N mineralization being 44 kg/ha/year for P rigida, 92 for L leptolepis and 112 for Q serrata, and percent nitrification ranging from 45% for P rigida to 90% for L leptolepis. Litterfall N inputs seemed to influence soil N mineralization. This study indicates that under a similar environment and soil type, N mineralization may differ by several-fold under the influence of different species.